1. Field of the Invention
The present invention relates to an optotype presenting apparatus arranged to present a test optotype for testing a visual function of an examinee's eye.
2. Description of Related Art
An optotype presenting apparatus arranged to display vision test optotypes (charts) on a display such as a liquid crystal display and present the optotype(s) to examinee's eyes has ever been known (for example, see Jpn. unexamined patent publication No. 2006-42978). The optotype presenting apparatus of this type is located in use at a 5 m distance or others for a far vision test.
Meanwhile, an electrically-operated apparatus is usually provided with a pilot lamp (an indication light) for indicating an energized state of the apparatus to a user. On the other hand, a trend in a display-type optotype presenting apparatus is shifting towards a small-size and low-profile design.
However, as a housing of the apparatus is smaller in size and profile, the pilot lamp is placed closer to the display. When the pilot lamp lights up near an optotype displayed on the display, examinee's attention tends to be distracted from the optotype. This case is likely to cause a decrease in test accuracy and an increase in test time. In a test in a dark room, particularly, the light of the pilot lamp is conspicuous. Especially during a binocular vision test, the pilot lamp placed close to the optotype is likely to act as a fusion stimulus.